Japanese laid-open patent application No. 2011-175316 describes a conventional machine tool has a machining chamber for machining a material, an illuminator provided in the machining chamber, and an NC unit for controlling a machining operation on the basis of an NC program. The conventional machine tool has a one-block stop mode in which the NC program is executed for only one block thereof, and then the machine tool stops its operation.
In the one-block stop mode, the operation of the NC program can be checked one block at a time. The conventional machine tool also has a manual execution unit for manually executing the NC program via a pulse signal generated in response to operation of a manually operated part such as a manual pulse handle, to operate the machine tool.